/Engine/Source/Runtime/InteractiveToolsFramework/Public/BaseGizmos/GizmoMath.h
Find the intersection of the ray defined by RayOrigin and RayDirection with the sphere defined by SphereOrigin and SphereRadius. Returns intersection success/failure in bIntersectsOut and the intersection point in SphereIntersectionPointOut
namespace GizmoMath { void GizmoMath::RaySphereIntersection ( const FVector & SphereOrigin, const float SphereRadius, const FVector & RayOrigin, const FVector & RayDirection, bool & bIntersectsOut, FVector & SphereIntersectionPointOut ) }